1. Technical Field
The subject disclosure relates to minimally invasive surgical procedures and apparatus, and more particularly to surgical instrumentation for performing surgery associated with the thoracic cavity.
2. Background of Related Art
It is well established that the performance of various types of surgical procedures using less invasive techniques and instrumentation has provided numerous physical benefits to the patient while reducing the overall cost of such procedures. One area, for example, which has experienced a great increase in the performance of less invasive procedures is in the area of heart surgery. In particular, coronary artery bypass graft (CABG) procedures have been performed using less invasive techniques with much success.
Access to the patient""s thoracic cavity for such procedures in the past was typically achieved by a large longitudinal incision in the chest. This procedure, referred to as a median stemotomy, requires a saw or other cutting instrument to cut the sternum and allow two opposing halves of the rib cages to be spread apart. U.S. Pat. No. 5,025,779 to Bugge discloses a retractor which is designed to grip opposite sternum halves and spread the thoracic cavity apart. The large opening which is created by this technique enables the surgeon to directly visualize the surgical site and perform procedures on the affected organs. However, such procedures that involve large incisions and substantial displacement of the rib cage are often traumatic to the patient with significant attendant risks. The recovery period may be extended and is often painful. Furthermore, patients for whom coronary surgery is indicated may need to forego such surgery due to the risks involved with gaining access to the heart.
U.S. Pat. No. 5,503,617 to Jako discloses a retractor configured to be held by the surgeon for use in vascular or cardiac surgery to retract and hold ribs apart to allow access to the heart or a lung through an operating window. The retractor includes a rigid frame and a translation frame slidably connected to the rigid frame. Lower and upper blades are rotatably mounted to the rigid frame and the translation frame respectively. Such a xe2x80x9cwindowxe2x80x9d approach requires instrumentation that can be inserted into and manipulated within the limited space available in and around the surgical site.
Therefore, a continuing need exists for more versatile and varied surgical instrumentation which facilitates performing surgical procedures in limited access cavities of a patient during less invasive surgical procedures.
The present disclosure addresses the above-noted needs while providing surgical instrumentation that has many unique features and advantages over the prior instrumentation. The presently disclosed surgical instrumentation provides greater versatility during surgical procedures which are less invasive than traditional procedures.
For example, in one embodiment, the present disclosure provides a mounting assembly for mounting a surgical instrument to a base, wherein a clip portion and a cover portion function together to retain the shaft of a surgical instrument therein and thereby fix the length of the instrument shaft relative to the base and an operative site. This is particularly advantageous in that during surgical procedures where free space in and around the surgical site is at a minimum, the presently disclosed mounting assembly facilitates positioning a surgical instrument relative to the surgical site so that only the minimum portion of the instrument is positioned in the sparse free space.
In an alternative embodiment, a mounting assembly for mounting a surgical instrument to a base is provided which includes first and second opposed mounting sections. The mounting assembly includes an instrument retaining area configured and dimensioned to removably retain the shaft of a surgical instrument therein.
In another aspect of the present disclosure, a surgical instrument is provided which includes a handle, a tool member, and an articulating arm which operatively connects the handle and the tool member. The articulating arm includes a number of arm segments and a number of reinforcing segments each of the various segments having a concave surface and a convex surface. The reinforcing segments have a maximum width which is less than a maximum width of the arm segments. In a particularly advantageous feature, the arm segments and reinforcing segments are arranged in a nested series to define a flexible column, wherein a cable extends from the handle through the a passageway in the segments to the distal end of the articulating arm.
In one aspect of the above embodiment, the reinforcing segments each includes a number of protrusions to facilitate making contact with the inner surface of the adjacent arm segment. In another aspect, each of the protrusions forms a tapered end.
In another embodiment, the present disclosure provides a surgical instrument including a handle having first and second relatively movable handle portions, a tool member, an articulating arm which operatively connects the handle and the tool member. The articulating arm includes a plurality of arm segments arranged in a series to form a flexible column. A cable is provided which extends from the handle through the passageway to the distal end of the articulating arm such that relative movement of the first and second handle portions to a first predetermined configuration causes the cable to be tensioned a predetermined amount. Finally, a tension adjustment mechanism is provided which includes an actuator and a slide housing operatively associated with the handle, such that upon movement of the actuator within a finite predetermined range of motion, the tension imparted in the cable may be incrementally adjusted and maintained at any magnitude associated with the predetermined range of motion of the actuator.
In yet another aspect of the present disclosure, a surgical instrument is provided which includes a handle having first and second relatively movable portions, and an articulating arm extending from the handle. The articulating arm includes a number of arm segments arranged in a series to form a flexible column, each of the arm segments defining an aperture therethrough such that a passageway is formed from a proximal end of the articulating arm to a distal end of the articulating arm. A cable is provided which extends from the handle through the passageway to the distal end of the articulating arm such that relative movement of the first and second handle portions to a first predetermined configuration causes the cable to be tensioned a predetermined amount. Finally, the present embodiment includes an end effector connecting assembly disposed at the distal end portion of the articulating arm. The end effector connecting assembly includes a housing, and a coupling member operatively connected to the distal end of the cable and movable relative to the housing from a closed position to an open position. The coupling member is operative to facilitate the removal or attachment of and end effector from the distal end of the articulating arm.
The present disclosure also provides the user with a uniquely advantageous surgical instrumentation kit including a surgical instrument having a handle, an articulating arm which forms a flexible column, and an end effector connecting assembly disposed at the distal end portion of the articulating arm. The coupling member is capable of retaining a connection portion of an end effector and when disposed in the open position. Preferably, the coupling member facilitates the removal or attachment of and end effector from the distal end of the articulating arm. The surgical instrumentation kit includes a number of interchangeable surgical tool end effectors each having a uniform connector portion for interchangeable engagement with the end effector connecting assembly of the surgical instrument. Finally, the surgical instrumentation kit includes a mounting assembly for mounting the surgical instrument to a base.